ATV used to be pretty popular, but that popularity may have fallen off. Slow Scan TV (SSTV) used to be popular on HF and you can still find guys operating SSTV around 14.230 MHz. I believe they are just sending photos back and forth. Fast Scan TV used to be popular on UHF and many major cities had an ATV repeater. In my area, the ATV repeaters are all gone because nobody was using them.